求幂(快速幂)

const long long MAX=100000;

模运算规律(分配律)

(a + b)% c = (a%c + b%c)% c
(a + b)% c = (a%c - b%c) % c
(a * b)% c =(a%c * b%c ) % c

普通法(定义法)

long long normalPower(long long base, long long power) {
	long long result=1;
	for(long long i=1; i<=power; i++) {
		result=(result*base)%MAX;
	}
	return result;
}

快速幂法

原理: ab=(a2)b/2 (注意区分b的奇偶)

long long fastPower(long long base,long long power) {
	long long result=1;
	while(power>0) {
		if(pow&1==1) {
			result=result*base%MAX;
		}
		power>>=1;
		base=base*base%MAX;
	}
	return result;
}

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转载自blog.csdn.net/The_Only_God/article/details/107317135